(written from a Production point of view)
Robert Schwertzer is the actor who played the Aenar physician in the Star Trek: Enterprise episode "The Aenar". As an extra, he received no credit for his appearance and was identified by the name tag of his costume, which was sold off on the It's A Wrap! sale and auction on eBay for US$200. 
This episode seems to be Schwertzer's only known on-screen role.